Automatic feed for machine tools and the like



July 10, 1934. v c s 1,965,867

AUTOMATIC FEED FOR MACHINE TOOLS AND THE LIKE Filed Oct. 1929 2Sheets-Sheet 1 I 03 70 Jj 607507 50 W fi- 6 36 *F/ July 10, 1934. F. wcK1,965,867

AUTOMATIC FEED FOR MACHINE TOOLS AND THE LIKE Filed Oct. 4, 1929 2Sheets-Sheet 2' 5 feed.

Patented July 10,- '1934- oNITEos A res pATENT OFFICE 1.9mm AUTOMATICFEED FQB MACHIINETOOLS 1 4 AND 'rnr: LIKE Harry r. Vickers, m-snseiu.cam. Application mom 4, im, .Serlal No. we s Claims. L (01. Ir-s2) Thisinvention has to do with anautomatic feed for use in machine tools, andth like, and it is an object of the invention to provide a practical,accurate, and inexpensive fluid pressure actuated The present inventionis': useful, generally, for

I ieeding or controlling movable elements such as.

carriages, heads, and like parts, found in numerous classes'of machines,apparatus. The in: vention is particularly usef and practical as apa isnot to be construed asliniitin'g or restricting the scope or range ofapplication of the invention.

his a' general object of the present invention to provide aieedfor amovable element wherebyv the element can be operated accurately and ch35 fectively' at .varying speeds or ineither direction,

' the invention being such that the element being fedcan be operated atvarious speeds when mov ingin a single direction and can be operatedbetween a very slow speed and a very high speed.

It is anotherobject otthepresent invention to provide a 'feed of thecharacter mentioned which is extremely accurate in operation, being.more accurate than mechanical feeds ordinarily involved in machinetools.

Another object of the present invention is to provide a feed of thecharacter mentionedwhich .is extremely simple and inexpensive ofmanuiacture and such that it can be applied to machime in variousmanners so that it does not interfere with other parts or becomecumbersome or inconvenient. i

- The various objects and features of invention will be best and morefully understood from the following detailed description of a typicalform and application-of the invention, througheompanying drawings inwhich:

Fig. 1 is a view showing a machine tool particularly suited foroperating 'a drill, or the like, and showing the i'eed'provided by thepresent invention applied to the tool for operating the drillcarryinghead. Fig. 2 is an de-' tailed sectional view showing a part of themechanism, being a viewtaken as indicated by line 2-4 onl'lg. lythepartsbeingshown in the baiplied to machine tools. In" applying theinven-- out which description reference is had to the acparallel to eachotherand suitably spaced so that they brace and effectively. operate thetool 081179 I anoed or unactuawd position. Fig; 3 is a view similartoFi'g. 2 the parts inr tion where the feed is in operation in onedirection. Fig.4isanenlargedendviewofcerta'inotthe parts illustrated inFig. i, being a view-taken asindicatedbylineHonI-lgl. Fig.5isan enlargedplanview taken as indicated by line 55 onF ig. 1..Fig.6isanenlargedviewillustratmg the valve operating means of the feed,

and Fig. '7 is an enlarged detail sectional view of g the valve of themechanism.

The machine tool illustrated in the drawings 1 includes, generally, abase 10, a work holder 11 mounted on the'base 10,'and a machine head 12.on the base 10 for driving a tool, say, for instance, a drill 13, orthe like. The'machine head 12 includes, generally, a body B in the formof a housing, a motor M mounted on the body, a movable tool carryinghead H supported from the body 3 through a spindle 8 so thatit can be umoved or 'reciprocated,-etc. The machine head 12 includes a suitabledriving connection between the motor M and carrying headjH wherebythetool holder 14 on the head is rotated. The

drive is preferably through the spindles. -The presentinvention is'notspecifically concerned 1 with the details otthemachine tool to which itis applied; for instance; it is not-concerned with the drive forrotating'the tool holder l4, and

therefore such "details have been omitted from a thepresent disclosure.-Numerousformsofmachinetooliandtypesofdrivesareempl y ingmachineryofthischaract'erandarefamiliarto those skilledintheart.

The present invention is concerned primal-iii headHtofeedstoolsuchasadrill13,orthe :with a feedmeans for p ratingthemovable like,-carried by the head H into and out of engagemerg with workin the holder 11. The presg ent invention provides,- generally. one ormore fluid pressure actuated mechanisms 1:, a control valve Y for themechanisms x, and means z for automatically operating the control valve.

In, the particular form and application or the two cylinder and pistonmechanisms x ing head H. The cylinders 16 of the mechanism inventionillustrated in the drawings there are 10 xare fixed to, for instance,they maybeformed on,theheadH,andareparallelwiththeaxisof-;

movement of the head, that is, they are parallel with the spindle s. Thepistons 1'1 '0! the mechanisms are slidably carried in the cylinders 16and are'iixed'on rods s which m m e is cylinders 16 and are connectedwith stationary parts, say, for instance, to the body B. In the valve.

form of the invention illustrated the rods 18 project from both ends ofthe cylinders through suitable packing glands 20. The rods 18 are fixedto the body B and thereforeoperate to'hold the pistons 17 stationary orin fixed position. With this arrangement relative movement between thecylinders and pistons results in movement of the cylinders and thereforemovement of the head H which connected with the cylinders.

The valve Y constitutes control means for the mechanisms X operable tocontrol the introduction and discharge of fluid under pressure to theends of the cylinders. In practice I provide a single valve Y for thevarious mechanisms X employed to operate the head'I-I. The valve Y maybe directly connected with any one of the mecha nisms X, in which casethecorresponding ,ends

- nature of a cylinder having a bore 37 slidably carrying the valve 36.The body 35 of the valve is preferably stationary with the movable ele-'ment of the mechanism X; for instance, it may be integral with thecylinder 16 as clearly illustrated in Figs. 2 and 3 of the drawings.

A fluid supply port 50 enters the middle portion of the body 35 and maybe supplied with fluid under pressure through a flexible conduit 51.fluid outlet port 52 is provided at one end of the body and connectswith a suitable flexible conduit 53 provided for conducting fluid fromthe It is to be understood that any suitable fluid under pressure, say,for instance, water or oil, may be supplied to the device through aconduit 51 ata suitable pressure and in a=suitable I quantity.

in the exterior-of the valve at points spaced from the 'chamber 62 tocooperate with the ports 60 and 61, respectively. The chambers 62, 60%and 61* are in the nature of recesses formed around the valve 36 and areproportioned and. located so that the valve has parts 60 and fil locatedover or opposite the ports 60 and 61, respectively. The chambers 60and-'61 are in communication with the central opening in the valve andare therefore in communication with the outlet,

port 52. The valve'parts above described are proportioned and related sothat the valve 36 may be positioned in a central or neutral positionwhere the parts 60? and 61 are related to the ports.60 and 61,respectively, so that fluid under pressure received through the port 50enters the ports 60 and 61 equally and as fast as it enters the portsitescapes to the chambers 60 and 61 discharging into the central openingof the valveand hence through the outlet port 52.

Fig. 20! the drawings illustrates the valve-in the. central or neutralpositionwhere the fluid is thus by-passed around the parts 60 and 61leaving the mechanism balanced with equal pressure at the two sides ofthe pistons.

Movement, of the valve 36 in either direction from the balanced or.neutral position will immediately disturb the equilibrium or balancedcondition at which the parts are all at rest and will cause morepressure to come on one side of the piston than the other with theresult that the mechanism is operated by fluid pressure; for example,upon movement of the valve 36 in the direction indicated by the arrowsin Fig. 3 the valve moves to the left in the body 35 allowing a greateramount of fluid from the chamber 62 to enter the port 60 than the port61, or, if the movement is great enough, allowing all of the fluid toenter the port 60 while the port 61 is uncovered to the chamber 61,allowing free exhaust of fluid through the port 61 to the outletport 52.With the valves thus moved to the left, fluid under pressure enters thecylinder 16 at the left-hand end of the piston 17 and is allowed toescape from the cylinder at the right-hand end of the piston with theresult'that the cylinderv is; moved by fluid pressure to the left withreference to the piston, or in the direction in which the valve 36 ismoved. When the movement of the valve ceases, the fluid pressure actingon the mechanism in the manner just described will continue to move oroperate the mechanism until it has moved the parts to the'relativepositioning shown in Fig. 2 where the parts are balanced, and no furthermovement takes place. If the valve is moved in the opposite direction,that is, to the right, the direction of flow is reversed from that abovedescribed with the result that the cylinders are moved to the rightrelative to the pistons. This movement likewise will continue until thevalve stops, whereupon fluid pressure will actuate the parts until theyare related, as shown in Fig. 2, where all parts are balanced and themechanism remains at rest.

The means Z provided by the present invention for controlling the valve36 operates to move the valve in a manner to cause the fluid pressureactuated mechanisms to move the head H in a deflnite predeterminedmanner. The means Z includes, generally, a mechanism for reciprocatingthe valve stem 70 in a predetermined manner, and in the preferred formof the invention it includes a cam mechanism. ,In the form of theinvention illustrated the cam mechanism includes a revolving cam 71having a cam slot or groove 72,'and a cam 1 follower '73 having a partoperating in the groove 72. The cam 71 may be carried on and driven by aspindle 74 suitably operated from the drive within the body B; forinstance, operated in definite speed relation to the tool carrier 14 onthe head H. The cam follower 73 is fixed on the valve stem 70. The camslot 72 in the cam '71 is generated or formed around the cam 71 toimpart the desired reciprocatory motion to the valve stem '70. It willbe obvious that the cam mechanism may be provided to operate the valvestem in any suitable manner, that is, in either direction and at variousspeeds either constant speeds or varying speeds; for example, in thecase of operating a tool such as a drill, the cam may be made so thatthe head H moves to advance the drill against thework at the to thevalve Y. With the parts properly com within the scope of the followingclaims:

structed and fitted, the head n can be controlledwithin a very smallfraction of an inch, making the feed suitable for. precision work.-Having described only a typical, preferred form and application of my.invention, I do not wish to limit myself to the specific details setforth, but wish to reserve to myself any changes or variations that mayappear to those skilledin the art or fall-- Having described myinvention, I claim:

1. In a machine tool, two relatively movable elements, one a toolholder, the other a work holder, drivemeans torotate one of saidelements, fluidpressure actuated feed means for causing reciprocation ofone of said elements, a control valve controlling direction and rate offlow of fluid to the feed means and moving substantially with. thereciprocated element and including a reciprocating part'in constanttimed" driving relation with the drive-means to have a definite timerelation with the drive means whereby the flow of fluid through thecontrol is determined by the difierence between the movev ment ofsaid'part and the reciprocated element. 25

elements, one a tool'holder, the other a work 2. In a machine tool, tworelatively movable elements 1 3. In a machine tool; two relatively.movable elements, one a tool holder, the other a work holder, drivemeans to rotate one of said elements, fluid pressure actuated feedmeans; for causing reciprocation .of one of said elements, acontrolvalve for the feed means including a valve part fixed to thereciprocated element and a movable valve part in, constant dri 'anddefinite time relation with the drive means and cooperating" with thefirst mentioned valve part whereby the flow of-fluid through the controlvalve is determined by the difference between the movement of the lastmentioned part and the reciprocated clement. r

.4. Ina machinetool, two elements, one to be rotated and one to bereciprocated, drive means for rotating one element, fluidpressureactuated means for reciprocating one element, a control, for saidpressure actuated including, a

valve element translated by the drive means in accordance with thedesired reciprocatory movement tohave a definite time relation with thedrive means and a second valve element infixed relation tothe'reciprocated element and related to the first mentioned valveelementwhereby the flow of fluid is controlled by the diflerence be-'tween the respective movements of said elements.

5. In a machine tool, two elements, one a work 7 holder, the other atool holder, drive means for rotating one element, a cylinder and pistonmechanism for-reciprocating one element, mea'ns for supplying operatingfluid ,under pressure to saidmechanism to cause reciprocation betweenthe cylinder and piston, means for controlling the operatingfluidforcontrolling the direction and speed of operation of .said mechanism, anda direct positive operating connection between the said drivemeans andthe fluid controlling means to operate, the fluid controlling means indefinite time relation to said drive means.

[6. In a machine tool, two elements,-one awork holder, the other at'oolholder, drive means meansfor reciprocating'the other element, the

cylinder of said means beingmovable with said other elementfmeans forsupplying operating fluid under pressure to the cylinder tocausereciprocation of the said other element, and means for controllingthe direction and rate of flow of the operating fluid under pressure. tothe cylinder, the last mentioned means including a valve element fixedto the reciprocated element, a. movable valve element cooperating withthe first mentioned valve element, and cam j'for rotating one element,cylinder and piston means actuated by. the drive means-for moving themovable valve elg'i'n entwhereby 'the'flow of operating'fluid'iscontrolled by the difference between'the respectivemovements-ofsaid ele- HARRY}.

